Search

Compared with the traditional keyboard and mouse input method, touch screen technique has high convenience for users. With the development of technology, touch screen is widely application in various electronic products because of their high transmittance, clear images, and convenient operation. This review mainly introduces the optical clear adhesive (OCA), liquid optical clear adhesive (LOCA), and the most commonly used LOCA ultra violet (UV)‐curable adhesives. Preparation and performance of UV‐curable adhesives are deeply explored. The structure of touch screen, such as one glass solution (OGS), on‐cell and in‐cell is discussed. Moreover, lamination process includes full lamination and non‐full lamination is also discussed. This review introduces the alignment technique comprise mechanical alignment technique and non‐mechanical alignment technique (such as machine vision) and laminating equipment. The recent development and existing problems with the touch screen lamination process are discussed. Furthermore, this review describes the latest developments in the adhesive of touch screen lamination process and predicts possible future development trends, which could provide references for subsequent research work. This review mainly introduces optical clear adhesive (OCA), liquid optical clear adhesive (LOCA), and ultraviolet (UV)‐curable adhesives and further explores the preparation and properties of these adhesives. The structure of touch screen, lamination process, alignment technique, recent development, and existing problems with the touch screen lamination process is discussed. Furthermore, the development trends of touch screen lamination process are predicted.

Electric discharge machining (EDM) can be used to cut complex parts and hard materials, making it one of the most popular machining processes today. However, the energy efficiency of EDM is low compared with conventional methods such as turning, milling and grinding. In addition, the gas and noise emissions of the EDM process affect the environment and the health of operators. This paper reviews the research trends in the latest sustainable techniques in EDM. First, a detailed review of existing EDM techniques for enhancing energy efficiency conducted. The review considers three aspects: energy distribution, the relationship between process parameters and specific discharge energy, and the effects of external field assistance. Second, the dry-EDM process-a clean manufacturing technique is introduced and its environmental impact is discussed. The machining performance indicators of dry-EDM, such as the material removal rate, tool wear ratio, surface topography, and microstructures, are compared with those of conventional EDM. Next, the indicators of gas and noise emissions in EDM are proposed to evaluate the sustainable manufacturing process. The relationship between the process parameters and emission indicators is reviewed, and multi-optimization considering machining noise is discussed. Finally, the impact of sustainable techniques in EDM on the environment, society, and economy are discussed, as well as the application costs of these techniques. Some directions for future research are also proposed.

Electrical discharge machining (EDM) is a nontraditional processing technology that can be used to process materials with a high melting point, high strength, high hardness and low brittleness. Kerosene, as a common dielectric, produces aerosol and toxic gas at high temperatures, which seriously affects the health of operators and air quality. In this study, edible vegetable oils such as sunflower oil, rapeseed oil and peanut oil were used as dielectric to improve the sustainability of EDM. The Taguchi method was used to design experiments, and the effects of vegetable oils with different viscosities on machinability during EDM were discussed from the perspective of mechanism. The machinability was evaluated with the material removal rate (MRR), energy efficiency per unit volume (EEV) and surface roughness (Ra). In addition, the debris diameters of different vegetable oils after processing were studied by using a super depth-of-field optical microscope. The results showed that the MRR of rapeseed oil was 28.9% higher than that of sunflower oil and 25% higher than that of peanut oil. In terms of the MRR, Ra and EEV, rapeseed oil also had obvious advantages because of its high viscosity. In addition, because of the high viscosity of rapeseed oil, the distribution proportion of large fragments was obviously larger than that of the other two oils. The proportion of debris larger than 35 μm in rapeseed oil was 8.21% and that of sunflower oil was only 2.79%. Therefore, vegetable oils can be used instead of a kerosene dielectric to improve the sustainability of EDM and to realize green manufacturing.